1. Field of the Invention
The present invention relates to a refrigerant condenser with an integral receiver employed in what is generally termed a refrigeration cycle, and is favorable for employment in an automotive air-conditioning apparatus where for example an amount of refrigerant recirculation fluctuates greatly.
2. Description of the Related Art
Conventionally, a receiver and a condenser have been disposed individually and independently in a refrigeration cycle of an automotive air-conditioning apparatus. For this reason, cost reduction due to a reduction in the number of parts has been difficult, and because the receiver and the condenser mutually occupy installation space, there has existed the problem of being unable to accommodate demand for space savings. In this regard, providing a vapor-liquid separation chamber to play the role of the receiver on an outlet-side header portion of a condenser is proposed in Japanese Patent Application Laid-Open No. 4-320771.
These prior arts are explained in FIGS. 8 and 9, wherein a tubular body 33 of a receiver 9 is integrally brazed to a tank plate 32 of a header 16 of a refrigerant outlet side of a condenser 3. In performing this brazing, to ensure brazing strength of the tank plate 32 and the tubular body 33, the brazing location of the two members is formed mutually at flat portions 32a and 33a.
However, it is acceptable for the height of the receiver 9 to be normally low in comparison with the height of the condenser 3, and so the flat area 33a comes to be formed over the entire surface in the lengthwise direction of the tubular body 33 on the receiver 9, whereas the flat portion 32a is formed on a portion in the lengthwise direction of the tank plate 32 on the receiver 3.
The foregoing tank plate 32 and tubular body 33 are formed by pressing a metal such as aluminum, but at that time, the tubular body 33 of the receiver 9 forms the flat portion 33a over the entire surface in the lengthwise direction thereof, and so the circumferential cross-sectional length is identical for any section, and no particular problem occurs in pressing.
However, it has been determined through prototyping and investigation by the inventors that the problem described hereinafter occurs at the header 16 of the condenser 3.
Namely, because the flat portion 32a must be formed on a portion (central portion only) in the lengthwise direction Of the tank plate 32 at the header 16 of the condenser 3, circumferential cross-sectional length becomes different at an existing portion and nonexistent portion of the flat portion 32a. That is to say, the circumferential cross-sectional length becomes small at an existing portion of the flat portion 32a, and the circumferential cross-sectional length becomes large at a nonexistent portion of the flat portion 32a.
Because two portions in which the circumferential cross-sectional length varies in size coexist in the length-wise direction of the tank plate 32 of the condenser 3 in this way, it has been determined that aluminum material does not flow smoothly at the flat portion 32a during press working, a state of excess material is obtained, this causes "wrinkling" 32a' indicated in FIG. 9 to occur on the flat portion 32a of the tank plate 32, and it becomes difficult to maintain the flatness of the flat portion 32a.
Refrigerant passage holes (not illustrated in FIGS. 8 and 9) are provided in the flat portions 32a and 33a of the foregoing tank plate 32 and tubular body 33, and so if the flatness of this passage hole perimeter is degraded, brazing performance of this portion becomes poor, and a problem of proneness to refrigerant leakage is caused.